On Monday, the day after he debuted as a kickoff returner against the Broncos in the third preseason game, the undrafted rookie said he’d politely lobbied to expand his role this summer. Owusu averaged 26.6 yards on 78 kickoff returns at Stanford and tied a Pac-10 record as a sophomore with three returns for touchdowns (94, 91 and 85 yards).

“I try to let them know that I want to contribute in any way I can on special teams and part of what I can help the team with is returning kicks,” Owusu said. “I think I do that well. It’s great to go out there and get an opportunity to do that.”

Two days after the preseason opener, Jim Harbaugh was at a loss when asked why Owusu, a player he’d coached for three years at Stanford, wasn’t among the players returning kickoffs in training camp.

“It’s a valid question,” Harbaugh said.

At some point, Owusu provided a gentle nudge, which perhaps provided the impetus to send him back deep Sunday. Owusu went back to field at least two kickoffs, but none of the 13 kickoffs in the game were returned – a nod to Denver’s mile-high altitude. Owusu isn’t listed as a kickoff returner on this week’s depth chart, which has Ted Ginn, Kendall Hunter and LaMichael James as the top three returners.

Owusu is presumably No. 4. James didn’t travel to Denver due to an ankle injury.

Owusu, who is likely battling to earn a spot on the practice squad, has caught four passes for 40 yards during the preseason. He hopes to have a chance to add to those totals in the preseason finale Thursday after a quiet afternoon in Denver. Owusu wasn’t targeted during a game in which the 49ers threw just 16 passes.

For Owusu, whose speed is his biggest asset, any chance to touch the ball — as a returner or a receiver — could significantly enhance his future job prospects.

“This is a big week for me, playing against the San Diego Chargers,” he said. “That’s what you’ve got to look forward to. You can’t look back at other games saying ‘What if?’ This game is the most important game now. You’ve got to go out there and play the best you can.”